Candles have been used as religious symbols in churches for many hundreds of years. An array of such candles is commonly provided in many churches which may include several hundred candles in closely spaced relation.
For esthetic purposes, the visual effect of the illumination provided by the candles should be enhanced as much as possible. At the same time, some provision must be made for protecting against the fire hazard inherent in the open flames. For this reason, each candle is commonly held in an individual container which prevents run-off of hot wax and protects the underlying support and any nearby articles from the flame.
Containers providing the best compromise between the esthetic desirability of a visible flame and the safety requirement of an enclosed flame have been glass containers. These may be provided in various colors and varying degrees of transparency to offer the desired appearance. However, such containers are subject to breakage from impact or the heat generated by the candle flame. Thus, although glass containers do provide the necessary flame and heat containment as long as they remain intact, a definite safety hazard is presented by their susceptibility to breakage. The glass containers become extremely brittle after several hours of exposure to heat and carbon deposits from burning candles. In addition to the safety hazard, breakage of the containers presents maintenance problems (i.e., cleaning up the broken glass, wax, etc.) and adds significantly to upkeep costs both in providing the necessary maintenance services and in buying replacement containers. While containers made of materials other than glass have been provided, the esthetic requirement of a visible flame or illumination has made opaque containers entirely unsuited to such applications.